Method of making blanks for flexible bolts.



E. I. DODDS.

LE sons.

, Patented Oct. 17,1916.

LZ////%%/vv\ 7 /%%//I 3 UNITED? T 'mme w ETHAN I. DODDS, or PITTSBURGH, PENNsYLvANIA, ASSIGNOR To FLANNERY-BOLT COMPANY, OF PITTSBURGH, PENNSYLVANIA.

METHOD'OF MAKING BLANKS FOR FLEXIBLE BOLTS.

To all whom it may concern:

Be it known that I, ETHAN I. DoDDs, a citizen of the United States, and a resident ofPittsburgh, in the county ofAllegheny and State of Pennsylvania, have invented certain new and useful Improvements in Methods of Making Blanks for Flexible Bolts; and I do hereby declare the following to be a full, clear, and exact description of the invention, such as will enable others skilled in the art to which it appertains to make and use the same.

My invention relates to an improvement in the method of making blanks for flexible bolts, the object being to simplify the process of manufacturing the blanks whereby the cost of production of the bolts will be reduced and the output increased.

The invention consists,in folding a hat bar, oblong in cross section, into a series of folds without welding the meeting faces, rolling the bar thus produced into cylindrical shape, and then twisting the same, thus producing a bar. composed of three members, each side member being united to the central member at one end only.

In the accompanying drawings, Figure l is a view in end elevation of a flat slab from which the bars are made; Fig. 2 shows the same within the bending rolls; Fig. 3 shows one half of said bar bent as in Fig. 2, and folded onto itself; Fig. 4 is a View in cross section of the bar after it has been rolled into cylindrical shape; Fig. 5 is a view of a modification and Fig. 6 is a'view in elevation of the slotted bar twisted spirally.

1 represents a fiat slab of such width and thickness that when bent and severed longitudinally, each half will be substantially of the same cross sectional area, as the round bar from which the bolt blanks are made, so that but slight rolling will be necessary to reduce the bars to proper size and shape. This slab 1 may be of any length that can be conveniently handled, and after being heated is passed between the rolls 2 and 3 which bend the slabs into the fluted or V- shapes shown in Fig. 2, and displace the metal at the several bends as at 4, and distribute it to the parts between said bends, thus leaving the bends somewhat thinner than the parts intermediate the bends.

Each slab 1 forms two bars, and after the slab has been rolled, as in Fig. 2, it is severed longitudinally into two sections each Specification of Letters Patent.

Patented Oct. 17, 1916.

I Application filed February 25, 1915. Serial No. 10,604.

substantially N shape and composed of a central member 0 and two side members .6. The members of each section are then passed between rolls, or within a press or other flattening machine, and compressed so as to close up the spaces between the several members without welding the adjacent faces, as

shown in Fig. 3, after which the bar is passed between rolls and reduced to cylindrical shape as in Fig. 4. The bar thus formed, is still composed of a central member 5 and two side members 6, each of the latter being united to the central member at the point 7 only, or the bar is in effect slotted at opposite sides as at 8, the two slots being off the center and extending more than half way through the bar. After the bars have been thus formed, they are twisted longitudinally from end to end so that the slots will be in the form of spirals extending from end to end of the bar.

I Instead of forming two bars from a single slab as above described, the slabs may be of a size for a single bar as shown'in Fig. 5.

To make bolts from the bar, the latter is reheated and is fed to a machine which upsets the head and cuts off the blank.

By twisting the bar from which the bolt blanks are cut, the twist will be constant and uniform from end to end, and consequently uniform in the blanks that are cut from the bar. The upsetting of the heads, welds the wall of the slots at the heads, but

leaves the walls of the slots in the shanks disconnected thus permitting the shanks to give or yield, as is well known in the type of bolt.

After the blanks have been cut from the bar, the threads are then either hot or cold rolled or they may be cut.

Having fully described my invention what I claim as new and desire to secure by Letters-Patent, is

1. The method herein described of making bolt blanks consisting in bending a slab transversely into side and central members, closing the side members formed by such bending onto the central member and rolling the bar thus formed into cylindrical shape.

2. The method herein described of making bolt blanks consisting in bending a slab transversely into side and central members closing the side members formed by such bending onto the central member, rolling the bar into cylindrical shape and twisting nally into a plurality of bars each substantially' N-shape in cross secti0n,'and rolling each bar thus formed into cylindrical shape.

4. The method herein described of making bolt blanks consisting in bending a slab transversely into a series of substantially N- shape sections, dividing the slab longitudinally into a plurality of bars each substantially N-shape in cross section, rolling each bar thus formed into cylindrical shape and twisting it spirally from end to end.

In testimony whereof, I have signed this specification in the presence of two subscribing Witnesses.

v ETHAN I. DODDS. Witnesses:

F. H. ALLISON, EDWIN S. RYGE.

. Copies of this patent niay be obtained for five cents each, by addressing the Commissioner of Patents.- 7 Washington, D. 0. i a a 

